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1.
Conclusions An efficient method for the synthesis of ,,-trihydropolyfluoroalkyl chlorophosphates is by reacting ,,-trihydropolyfluoroalkyl dichlorophosphites and bis-(,,-trihydropolyfluoroalkyl) phosphites with sulfuryl chloride. It has been found that in three-coordinated polyfluoroalkyl phosphites, the high electronegativity of the polyfluoroalkyl groups hinders cleavage of the latter on reaction with sulfuryl chloride, thereby facilitating the formation of oxidation products.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 146–149, January, 1988.  相似文献   

2.
Elemental sulfur reacts with ketones and gaseous ammonia at room temperature yielding thiazoline-3 in excellent yields. Under the same conditions elemental selenium does not react at all. Attempts using the known techniques which have been applied in improving the reactivity of slowly reacting ketones in thiazoline-3-synthesis have been unsuccessful (Exp. No. 1–17). The reaction of -halogenketones with sodiumhydrogenselenide to synthesize -hydroselenoketones gives only the original ketones and selenium in almost quantitative yields (No. 18–23). The same is observed with -haloketones and sodium ore magnesium-diselenides (No. 24–45). The explanation of these unexpected results is the strong reducing power of the hydrogenselenide (No. 46–52). Even -bromoketones with activated bromine (i.g. by phenyl groups) were reduced by sodiumhydrogensulfide giving red undefinite oils. However, -chloroketones give -mercaptoketones in excellent yields (No. 53–61). Hydrogenselenide reduces -mercaptoketones to sulfur and ketones in the presence of triethylamine (No. 62–67). Also the transformation of -selenocyanketones to ,-diketodisenides by alkali or the oxidative hydrolysis of selenium-BUNTE salts does not work and gives elementary selenium only. Studies about the concomitant reaction of elementary selenium and ethylenimine on ketones were continued (No. 68–82).
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3.
The composition of the mono- and sesquiterpenoids from the oleoresin of the Khingan fir has been studied. Thirteen monoterpenoids have been identified — bornyl acetate, -terpenyl acetate, geranyl acetate, citronellyl acetate, -fenchyl acetate, linalool, geraniol, terpineol-4, -terpineol, -fenchol, borneol, sabinene hydrate and thymol methyl ether; and 19 sesquiterpenoids — -longipinene, longicyclene, longifolene, -copaene, -ylangene, sibirene, -and -selinenes, - and -cadinenes, -muurolene, caryophyllene, -humulene, - and -bisabolenes, ar-curcumene, nerolidol, bisabolol, and -cedrol. The crystal structure of -cedrol has been investigated by x-ray structural analysis.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 41–45, January–February, 1985.  相似文献   

4.
From the epigeal organs of the great march marigold (family Ranunculaceae) two triterpene glycosides, a tetra- and a pentaoside of hederagenin, have been isolated. Their chemical structures have been established by chemical methods of investigation and by1H and13C NMR spectroscopy. Glycoside G is hederagenin 3-O--L-arabinoside 28-O-[O--L-rhamnopyranosyl-(1 4)-O--D-glucopyranosyl-(1 6)--D-glucopyranoside]. Glycoside I is hederagenin 3-O-[O--D-glucopyranosyl-(1 2)--L-arabinoside 28-O-[O--L-rhamnopyranosyl-(1 4)-O--D-glucopyranosyl-(1 6)--D-glucopyranoside].I. G. Kutateladze Institute of Pharmacochemistry, Georgian SSR Academy of Sciences, Tbilisi, Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 229–236, March–April, 1988.  相似文献   

5.
Conclusions Due to thearom–gsC-Hal* interaction, the magnetic susceptibility ellipsoids of -haloalkylbenzenes, with the exception of ,'-p-xylylidene bromide, undergo rearrangement of the semimajor axes with a decrease in the diamagnetic component in direction 1, 4 and along the axis of symmetry of the electrons in the ring.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No No. 7, pp. 1552–1557, July, 1986.  相似文献   

6.
A new withasteroid — vamonolide — has been isolated from the epigeal part ofPhysalis angulata L. (Solanaceae). On the basis of spectral characteristics, its structure has been established as 5,14-dihydroxyl-l-oxo-6,7-epoxy-20R,22R-with-2-enolide.Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 856–858, November–December, 1987.  相似文献   

7.
The isolation of four triterpene glycosides from the roots of the dahurian anemonePulsatilla dahurica (Fisch. ex DC) Spreng, is described together with their identification, on the basis of chemical transformations, spectral characteristics, and literature analogies, as hederagenin 3-O--L-arabinoside, hederagenin 3-O-[O--D-glucopyranosyl-(12)--L-arabinopyranoside], hederagenin 3-O--L-arabinopyranoside 28-O-[O--L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranoside], and hederagenin 3-O-[O--D-glucopyranosyl-(14)--L-arabinopyranoside] 28-O-[O--L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranoside].Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, Nos. 3,4, pp. 349–356, May–August, 1992.  相似文献   

8.
A preparative method for 9a-hydroxylation of 5-3-hydroxysteroids using the fungi ofCircinella sp. 10Kh-1220 not capable of modifying theA ring has been developed. It is established that the yields of the main and the side products greatly depend on the transformation conditions, mycelium age, and the structure of the steroid substrate. Under the optimal transformation conditions novel 9-hydroxysubstituted derivatives of androstenolone, pregnenolone, 16-dehydro-16,17-epoxy-, and-16-methoxypregnenolone have been obtained in 36–80 % yields.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 737–743, April, 1994.  相似文献   

9.
Four new polyhydroxysteroids, 5-cholesta-3,5,6,15,16,25,26-heptaol, 24-ethyl-5-cholesta-3,5,6,15,28,29-heptaol-29-sulfate, (22E)-24-methyl-5-cholest-22-ene-3,5,6,15,25,26-hexaol-26-sulfate, 24-propyl-5-cholesta-3,5,6,8,15,28,29-heptaol, and the known 5-cholesta-3,5,6,15,16,26-hexaol, have been isolated from the starfishCtenodiscus crispatus.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1821–1825, October, 1994.  相似文献   

10.
The crystal structure of the sesquiterpene lactone pyrethroidinin, in the independent part of the elementary cell of which there are two molecules, has been determined by x-ray structural analysis. A stereochemical analysis is given of the results, and the structure 3,10-dihydroxy-1,6,7(H)-guaia-4(5),11(13)-dien-6,12-olide is proposed for pyrethroidinin.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Institute of Bioorganic Chemistry, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 50–55, January–February, 1988.  相似文献   

11.
Derivatives of -alkyl-, -alkylidene-, and -hydroxymethylene-2-oxabicyclo[3.3.0]-6-octen-3-one were obtained. The possibility of functional substitution of the bicyclic -lactones at the position to the carbonyl group was thereby demonstrated.For Communication 29, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1621–1630, December, 1991.  相似文献   

12.
Conclusions 1. A. new route for the synthesis of optically active ,-diglycerides has been developed.2. D- and L-, -Distearins and D-, -dilinolenin have been synthesized from the readily accessible L- and D--O-tritylglycerols.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 4, pp. 210–214, 1969  相似文献   

13.
The syntheses of the 2-anilinocyclopentanones2 a–2 e in yields about 50% by reaction of 2-chlorocyclopentanone with 4-chloroaniline, N-methyl-4-chloroaniline, ,,-trifluoro-3-toluidine, N-methyl-,,-trifluoro-3-toluidine and 3,4,5-trimethoxyaniline, are described.  相似文献   

14.
Ethyl -halo--nitropropionate and -butyrate were prepared by alkylating ammonium salts of ethyl bromo- and chloronitroacetates. The addition of alkyl acrylates to alkyl chloronitroacetates or their salts gives dialkyl -chloro--nitroglutarates. Sodium salts of ethyl -nitro--sulfo--hydroxypropionate and -butyrate were obtained by the sulfodehalogenation of ethyl -chloro--nitro--hydroxypropionate and -butyrate with sodium dithionite. Esters of -amino acid hydrochlorides were prepared by the reduction of alkyl -chloro--nitrocarboxylates. The hydrogenation of alkyl nitrosulfoacetates leads to the corresponding disodium salts of alkyl aminodisulfoacetates and piperazine-2,5-dione.For communication 5 seeIvz. Akad. Nauk SSSR, Ser. Khim., 1990, 2012 [Bull. Acad. Sci. USSR, Div. Chem. Sci., 1990,39, 1826].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 872–876, May, 1994.  相似文献   

15.
Three new glycosides, D1, D2, and D3, have been isolated from the Far Eastern starfishDistolasterias nipon. They have been identified by chemical and physicochemical methods as 5-cholestane÷3,6,8,15,24-pentaol 3,24-di-O--D-xylopyranoside, t-cholest-22-ene-3,6,8,15,24-pentaol 3,24-di-O--D-xylopyranoside (II), and 5-cholestane-3,6,8,15,24-pentaol 24-O--D-glucopyranoside 3-O--D-xylopyranoside (III).Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 250–255, March–April, 1987.  相似文献   

16.
The influence of chelating agents on the separation factor, , of lithium isotopes separation was studied by ion exchange elution chromatography. Eluents contained the chelating agent having different number of coordination sites. The chelating agents used in eluent were Na-glycine (Na–Gly), 2Na-iminodiacetic acid (2Na-IDA), 3Na-nitrilotriacetic acid (3Na-NTA), and 4Na-ethylenediaminetetraacetic acid (4Na-EDTA). The ion exchanger was Dowex 50W-X8, sulfonic acid type, sodium form. As a result,6Li was enriched in resin phase, and7Li was in solution phase. The separation factor, , was gradually increased with increasing number of coordination site (=1.0022–1.0038) at the same distribution coefficient and with increasing distribution coefficients (=1.0017–1.0026) at the same concentration of chelating agents.  相似文献   

17.
Two new steroid glycosides, which have been called echinasterosides B1 and B2 have been isolated from the starfishEchinaster sepositus. Using chemical transformations (methylation, hydrolysis) and also spectral methods (1H and13C NMR spectroscopy and GLC-MS) the complete chemical structure of B1 has been established as 15-acetoxy-5-cholestane-3,4,6,8,24-pentaol 24-O[O-(2)O÷ methyl--D-xylopyranosyl)-(13)--L-arabinofuranoside] (I) and that of glycoside B2 as 5-cholestane-3,4,6,8,15,24-hexaol 24-O-[O÷(2-O-methyl--D-xylopyranosyl)-(13)--L-arabinofuranoside] (II).Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Pirodnykh Soedinenii, No. 2, pp. 246–249, March–April, 1987.  相似文献   

18.
-Cyclodextrin having cinnamamide at 6- or 3-positions (6-CiNH--CD, 3-CiNH--CD) and -cyclodextrin with cinnamamide on 6-position (6-CiNH--CD) have been prepared. Supramolecular structures were formed in the solid state or aqueous solutions and characterized by measurements of NMR and vapor pressure osmometry (VPO). The results indicate that 6-CiNH--CD formed insoluble supramolecular polymers in the solid state, while 6-CiNH--CD and 3-CiNH--CD formed supramolecular complexes in aqueous solutions. 6-CiNH--CD was found to form a dimer in an aqueous solution. 3-CiNH--CD formed intermolecular complexes to give supramolecular polymers. The differences of the position of guest part on cyclodextrins caused to give a variety of supramolecular structures in aqueous solutions.  相似文献   

19.
Proofs are given of the structures of two new glycosides of the furostan series isolated from the leaves of the plantNolina microscarpa S. Wats. (family Dracaenaceae). Nolinofuroside D is (25S)-furost-5-ene-1,3,22,26-tetraol 1-O--D-galactopyranoside 26-O--D-glucopyranoside (I), and nolinofuroside F is (25S)-furost-5-ene-1,3,22,26-tetraol 1-O--D-fucopyranoside 26-O--D-glucopyranoside 3-O--L-rhamnopyranoside (VII). The latter was characterized as its 22-O-methyl ether (VIII). Nolinofuroside E (IV) has the structure of (25S)-furost-5-ene-1,3,22,26-tetraol 26-O--glucopyranoside 1-O-[O--L-rhamnopyranosyl-(12)--D-fucopyranoside], which followed from the structure of the fermentation product (VI). The products of the fermentation of the above-named compounds were present in the plant in only trace amounts. Only one of them — nolinospiroside D (III) — has not been described previously. This monoside of the spirostan series is (25S)-spirost-5-ene-1,3-diol 1-O--D-galactopyranoside.M. V. Frunze Simferopol' State University. Institute of Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 678–686, September–October, 1991.  相似文献   

20.
The known alkaloid tuguaconitine and a new base, which has been called akiramine, have been isolated from the epigeal part ofAconitum kirinense Nakai. The structure of akiramine as 4-acetoxy-1,8-dihydroxy-6,14,16-trimethoxy-N-ethylaconitine has been established by a study of its spectral characteristics.Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 498–501, July–August, 1999.  相似文献   

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